Lymphangioleiomyomatosis: a clinical review

Loss of Tuberous Sclerosis Complex 2 confers inflammation via dysregulation of Nuclear factor kappa-light-chain-enhancer of activated B cells

Background

Aberrant activation of mTORC1 is clearly defined in TSC, causing uncontrolled cell growth. While mTORC1 inhibitors show efficacy to stabilise tumour growth in TSC, they are not fully curative. Disease facets of TSC that are not restored with mTOR inhibitors might involve NF-κB. The study aimed to characterise NF-κB in the context of TSC.

Results

Enrichment of NF-κB-regulated genes was observed in TSC patient tumours, SEN/SEGAs, cortical tubers and a TSC tumour-derived cell line (621 - 101). Highlighting an inflammatory component of TSC, TSC cell models showed an elevated level of NF-κB and STAT3 activation. Herein, we report a dysregulated inflammatory phenotype of TSC2-deficient cells where NF-κB promotes autocrine signalling involving IL-6. Of importance, mTORC1 inhibition does not block this inflammatory signal to promote STAT3, while NF-κB inhibition was much more effective. Combined mTORC1 and NF-κB inhibition was potent at preventing anchorage-independent growth of TSC2-deficient cells, and unlike mTORC1 inhibition alone was sufficient to prevent colony regrowth after cessation of treatment.

Conclusion

This study reveals autocrine signalling crosstalk between NF-κB and STAT3 in TSC cell models. Furthermore, the data presented indicate that NF-κB pathway inhibitors could be a viable adjunct therapy with the current mTOR inhibitors to treat TSC.

Clinical, tomographic and functional comparison of sporadic and tuberous sclerosis complex-associated forms of lymphangioleiomyomatosis: a retrospective cohort study

Background

Lymphangioleiomyomatosis (LAM) is a rare disease that can occur sporadically (S-LAM) or associated with the tuberous sclerosis complex (TSC-LAM). The natural history of LAM is not completely understood, including whether there is a difference between the clinical courses of the two forms. This study aimed to compare the clinical, functional and tomographic features between S-LAM and TSC-LAM, and evaluate the annual rates of change in lung function.

Methods

This retrospective cohort study included patients with LAM followed up between 1994 and 2019. Clinical, functional and imaging variables were evaluated, and the lung cysts were automatically quantified. Quality of life and predictors of lung function impairment were accessed, and the annual rate of lung function decline was compared between S-LAM and TSC-LAM.

Results

Of the 107 patients included, 77 had S-LAM and 30 had TSC-LAM. Although patients with TSC-LAM had a higher prevalence of renal angiomyolipomas and neurological and dermatological manifestations, pulmonary function tests were similar. Patients with S-LAM had a greater rate of forced expiratory volume in 1 s decline and a higher extent of cysts. Pneumothorax, desaturation in the 6-minute walking test and a higher extent of lung cysts were predictors of functional impairment. A greater impact on vitality and emotional health was observed in the TSC-LAM.

Conclusion

Greater functional decline and a higher cystic extension were found in patients with S-LAM. Our study provides a broad clinical, functional and tomographic characterisation of patients with LAM, adding valuable information to the existing evidence to better understand the two forms of the disease.

Lymphangioleiomyomatosis with Tuberous Sclerosis Complex-A Case Study

Lymphangioleiomyomatosis (LAM) is characterized by lung cysts that cause lung deterioration, changes in the lymphatic system, and tumors in the kidneys. It mainly affects women of reproductive age and is a progressive disease. LAM can occur as an isolated disease or coexist with tuberous sclerosis (TSC). The source of LAM cells is unknown. Patients with confirmed LAM should be treated with an mTOR inhibitor, sirolimus, or everolimus. We present a case of LAM with TSC in a patient whose symptoms, including those in the lymph nodes and chyaloperitoneum, mainly concern the abdominal cavity.

Spontaneous Pneumothorax in a Young Female With Lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare disorder of abnormal proliferation of smooth muscle-like cells which results in the formation of thin-walled cysts and progressive lung destruction. It commonly presents with progressive dyspnea that is often associated with a history of pneumothorax or chylothorax particularly among females of reproductive age. In this report, we present a case of hydropneumothorax as the initial presentation of LAM in a 33-year-old woman, a rather rare presentation. We also discuss the pathogenetic mechanisms, the diagnosis, and treatment strategies using mTOR inhibitors like sirolimus.

Cystic Lung Disease Presenting as Recurrent Non-traumatic Chylothorax: Case Report and a Mini-Review

Malignancy and infections are the most common causes of recurrent chylothorax. Cystic lung disease, especially sporadic pulmonary lymphangioleiomyomatosis (LAM), is a rare condition that may manifest as recurrent chylothorax. We present a case of a 42-year female who presented with dyspnea on exertion secondary to recurrent chylothorax, requiring three thoracenteses within a few weeks. Chest imaging showed multiple bilateral thin-walled cysts. Thoracentesis revealed milky-colored pleural fluid, which was exudative and lymphocytic predominant. Infectious, autoimmune, and malignancy workup was negative. Vascular endothelial growth factor-D (VEGF-D) levels were sent for testing, which came back elevated (2001 pg/ml). A presumptive diagnosis of LAM was made based on recurrent chylothorax, bilateral thin-walled cysts, and elevated VEGF-D levels in a reproductive age group woman. Given quick reaccumulation of chylothorax, she was started on sirolimus. After initiating therapy, there was a significant improvement in the patient's symptoms, with no recurrence of chylothorax in the five years of follow-up. Awareness of different forms of cystic lung diseases is vital to establish an early diagnosis, which may prevent disease progression. Rarity and heterogeneity of presentation often make the diagnosis challenging, requiring a high degree of suspicion.

An Evidence-Based Update on the Potential Association between Rheumatoid Arthritis and Lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) represents an uncommon disorder characterized by cystic lung destruction and chronic respiratory failure. Lung damage caused by various mechanisms may represent a hypothesis for studying the association between LAM and rheumatoid arthritis (RA), which is the most prevalent autoinflammatory rheumatic disease and may affect the lungs as an extra-articular manifestation. Despite their distinct clinical presentations, the pathophysiology of both disorders includes dysregulated immunological function, abnormal cellular development, and inflammation. Current research suggests a potential relationship between RA and LAM, as some RA patients have been reported to develop LAM. However, the association of RA and LAM raises important therapeutic dilemmas. For this reason, the trajectory of a patient who was identified in our medical records as suffering from both LAM and RA, treated with many novel molecules and biological therapy, but with a negative outcome due to respiratory and multiorgan failure, has been exemplified. The delay in the diagnosis of LAM is due to a correlation between RA and LAM, worsening the vital prognosis and also hindering pulmonary transplantation. In addition, extensive research is essential for understanding the potential connection between these two disorders and discovering any similar mechanisms involved that may underlie their occurrence. This may contribute to the development of new therapeutic options that target shared pathways implicated in the pathogenesis of RA and LAM.

Lung transplantation for lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare cystic lung disease, associated with respiratory symptoms of dyspnea and spontaneous pneumothorax, along with various extra-thoracic manifestations. Often a progressive disease, albeit slowly, patients can develop chronic and severe respiratory failure and require supplemental oxygen. Lung transplantation (LTX) can offer improved duration and quality of life for patients with end-stage lung disease due to LAM. There are several unique considerations for LTX in LAM patients, and disease-specific complications of LAM prior to LTX can affect management decisions. Furthermore, there are several possible post-transplant issues specific to LAM. In this review, we discuss evaluation and management, disease-specific complications (both pre- and post-transplant), and outcomes for LAM patients undergoing lung transplantation.

Retroperitoneal Cystic Adenopecoma with Genetic Analysis: A Rare Neoplasm

Lymphangiomyomatosis is a member of the PEComa family, and usually involves the pulmonary parenchyma of middle-aged females. Infrequently, it may involve abdominal and retroperitoneal lymph nodes, and rarely it has been described to be associated with fallopian tube-type ciliated epithelium co-existing in one neoplasm. To increase our understanding of this unusual tumor, we describe the morphology and genetics of one case and review the literature. We present the case of a 50-year-old female found to have 12.5 and 7.7 cm cystic retroperitoneal masses, describe its unique pathological features and review the literature on the previously reported cases. Based on its unique morphological, immunohistochemical, and molecular features we propose the term adenoPEComa to represent this entity. This case represents a rare example of adenoPEComa with lymphangiomyomatosis of the lymph nodes. It is the first example that has undergone next-generation sequencing revealing a mutation in TSC2 making it a confirmed member of the PEComa family of tumors.

Long-term clinical course and progression of lymphangioleiomyomatosis in a single lung transplant referral centre in Korea

We aimed to describe the clinical features of lymphangioleiomyomatosis (LAM) in Korean patients and identify factors associated with progressive disease (PD). Clinical features of 54 patients with definite or probable LAM from 2005 to 2018 were retrospectively analysed. Common features were pneumothorax (66.7%) and abdominal lymphadenopathy (50.0%). Twenty-three (42.6%) patients were initially treated with mechanistic target of rapamycin (mTOR) inhibitors. Lung transplantation (LT) was performed in 13 (24.1%) patients. Grouped based on the annual decline in forced expiratory volume in 1 s (FEV₁) from baseline and LT, 36 (66.7%) patients exhibited stable disease (SD). All six deaths (11.1%) occurred in PD. Proportion of SD was higher in those treated initially with mTOR inhibitors than in those under observation (p = 0.043). Univariate analysis revealed sirolimus use, and baseline forced vital capacity, FEV₁, and diffusing capacity of the lungs for carbon monoxide are associated with PD. Multivariate analysis showed that only sirolimus use (odds ratio 0.141, 95% confidence interval 0.021-0.949, p = 0.044) reduced PD. Kaplan-Meier analysis estimates overall survival of 92.0% and 74.7% at 5 and 10 years, respectively. A considerable proportion of LAM patients remain clinically stable without treatment. LT is an increasingly viable option for patients with severe lung function decline.

Lung cancer is also a hereditary disease

Pathogenic genetic variants (formerly called mutations) present in the germline of some individuals are associated with a clinically relevant increased risk of developing lung cancer. These germline pathogenic variants are hereditary and are transmitted in an autosomal dominant fashion. There are two major lung cancer susceptibility syndromes, and both seem to be specifically associated with the adenocarcinoma subtype. Li-Fraumeni syndrome is caused by variants in the TP53 tumour-suppressor gene. Carriers are mainly at risk of early-onset breast cancer, sarcoma, glioma, leukaemia, adrenal cortical carcinoma and lung cancer. EGFR variants, T790M in particular, cause the EGFR susceptibility syndrome. Risk seems limited to lung cancer. Emerging data suggest that variants in ATM, the breast and pancreatic cancer susceptibility gene, also increase lung adenocarcinoma risk. As for inherited lung disease, cancer risk is increased in SFTPA1 and SFTPA2 variant carriers independently of the underlying fibrosis. In this review, we provide criteria warranting the referral of a lung cancer patient to the cancer genetics clinic. Pathogenic variants are first identified in patients with cancer, and then in a subset of their relatives. Lung cancer screening should be offered to asymptomatic carriers, with thoracic magnetic resonance imaging at its core.